Process of recovering salt from brine.



F. J. WOOD. PROCESS 0F RECOVERING SALT FROM BRINE.

APPLICATION FILED DEC.26, 1912. 1,152,777. PatentedSept. 7, 1915.

2 SHEETS-SHEET I.

F. J. W009-I PROCESS OF RECOVERING SALT FROM BRlNE.

APPLICATION FILED DEC.26,19 12. 1,152,777. Patentedsept. 7, 1915.

2 SHEETS-SHEET 2.

WHITESS ES: InvErL-l; DI'.

y ,narran stares rarnirr ortica.

OF NEW YORK, `N. Y., ASSIGNOR TO WOOD APPARATUS COMPANY, OF

NEW YORK. N. Y., A. CORPORATION OF NEW YORK.

PROCESS' RECOVERING SALT FROM BRINE.

sppncation'med Debember as, 1912. serial No. 738,708.

To all whom/it may concern Be it known that l, FRANK Ll. l/Voon, acitizen of the United States, residing in the city of New York, State ofNew York, have invented a certain .new and useful Improved Process etRecovering Salt from Brine, of which the following is a specification.

ln the recovery or" salt from aqueous solutions suclras spring'water orsea Water it may be desired to produce the salt in large or smallgrains, as each kind is of value in certain uses. For'. the productionof large grains thev generally accepted method is to vevaporate thebrine in large shallow open pans suitably heated, as by steam pipes. Thesurface being thus open' to the air rapid evaporation is effected at atemperature be .low the boiling point of the brine. As Ievaporationoccurs Wholly at the surface and there 1s no' agitation, no bubbles ofvapor Vrise through the liquid and in consequence `the precipitation isin the 'term of large crystals. Whem however, the evaporation iseffected in a closed pan and the brine is agitated, bubbles rise throughthe liquid. ln consequence the salt precipitation is in the form ofsmall grains.

The object of my invention is a process capable of providing both largeand small grains in one apparatus, one-or thev other kind being obtainedaccording to the temperature and pressures employed.

ln brief l employ a modification of the .open par. Without agitation anda multiple eiliect evaporating principle by which the heat fromV oneevaporation is conducted to succeeding evapora-tors to there constitutethe heating agent. in the heat used in the production of the large andsmall grainsalts than has heretofore been accomplished and theconsequent saving oi .tuel necessary to evaporate a given quariti'ir, ofbrine. n

In the accompanying drawings I'have Shoivnappropriate apparatus forcarrying out the, process, Figure l illustrating the entire system.inconventional arrangement. F 2 is a plan of the apparatus and pipingyslum/n in l. Figs. 3, ,'and 5, are details cii the grainers and F ig.6Y is an interio. View of the evaporator showing the 'method of adaptingit to this process.v

T'. i. l, is a steam boiler, 2, is an l to supply the entire motiveSpecification of Letters Patent.

Although l effect greater economy Patented Sept. 7, 1915.

power necessary to operate the moving or rotating pieces of mechanism.3, is a grainer cylindrical in shape in order to better adapt 1t tosustain a pressure. 4, is a grainer which is not intended to carry morethan a trilling amount of pressure; consequently it can be maderectangular in cross section. Although I am not going to consider thatthis grainer, 8, is under a pressure yet there is no reason Why it willnot operate at either a pressure that is somewhat above or below thepressure of the atmosphere. 5, is a grainer which is identical in everyrespect to grainer, Li, except that While in operation the brine itcontains is at a somewhat lower temperature than the brine inthegrainer, the dra-Wing shows the grainer, 5, to be of the same dimensionsas those of the grainer, 4, yet this is not of necessit lt might beadvantageous under some conditions to make the grainer 5, ofconsiderably greater cubical contents than thatV of grainer, 4. 6, is anevaporator adapted to be operated under a vacuum maintained by thevacuum pump, 50, which is in communication by thepipe 52 With thecondenser, 51. This condenser, 51, condenses vapor` flowing into it fromthe evaporator through 'the pipe, 54, by means ot' the cold water jet,58, supplied by the cold Water supply 55. The-condensing Water isfinally discharged from the condenser through the barometric tube, 56,into the hot Well, 57,

and from there to the sewer. -rlhe grainer,l

3, is heated by the steam pipes, 7, which are fed through theconnections, 63, and header', 20, with steam from either the live steamsupply direct from the boiler, l, flowing through the valve, 59, or theexhaust of the enginesupplied through the valve, G0, or if requiredthrough both these supply valves at the same time. The valve, 61,permits 'the exhaust to be opened tol the atmosphere inl case it isdesired to have the valve, 60, closed. The water of condensation whichaccumulates in the pipes, 7, flows out through the header, 2l, and theconnections, 62. These pipes, 7, are submerged in the brine the level ofwhich is kept con.

torations, il, fl, in thv pipes. lil. lll, 'the water is taken awayl'rom these troughs. S, h, through vonnvvtionsl and into thv header, l1.rl`his hvadvr. ll. delivers into the pipe, 1;). The water llowingthrough 'the perforated pipes. lo. lll. is supplied t'rom thehendel-,123. which is lied by the pipe, ll. partition, 17. extendsvertically l'rom thv level oi the brine to thv root ot thv grainvr-4but. hortZontally there is considerable space would bv a superfluousrepetition. 'l`he slight dili'erence between thv twti grainers lies inshapv ot' shell which is rectangular in cross section as is indicated bythe dotted lines, Il), Fig. Yt, and in the tan beingl placedsullicivntly low to vlvar the root' ot' the grainer which is lower inthe grainer, -Yl-, than it is in the grainvr. il. lso the pipes, 7, are,adapted to be heated by a llow o-t' hot water inst `ad otl steam.'.l`his hot water is led from thv troughs b, H, ol' graniet' il throughthe header. ll, out through the pipe, l2, into the header Ll() olgrainer l, and through the pipes T, tin thv grainer, 4,) bach in thvhvadvr, 2l. and into the pipe, 2 ot grainer il, then to the centrifugalpunp, 225, which lorcvs it up through the pipe, ll, to the header i3,and then to the pipes, 1l). rThus thetirst circuit olf the water iscompleted, The outlets, 25, discharge the Iwater of condensation `fromthe circulating y by leakage.

systems. Without this provision to get rid of the water which mustnecessarily accalmilate while the system is in operation the troughs, 8,8, would overflow into the brine'. There is no dilt'erence whatever inthe con struction of the grainer, 5, as cmnpared to the grainer, si. Thehot water drawn from the troughs, 8, 8, of the grainer, l, is circulatedby its centrifugal pump, 23, into the pipes, 7, ot' the grainer, 5, andthe hot water drawn from the troughs of the grainer, 5, is circulated bythe centrifugal pump ot this same grainer through the heating space, 27,of the evaporator, (i. rThis hot water being of a higher temperaturethan the boiling brine, in the vacuum space, 28, otA theevaporator-,fthe available heatl in this water is transmitted throughthe tubes, 2G, to the boiling brine. An air compressa-,25), is so placedand so connected to the grainers. 3 and 4, that it can be used to supplyair lost A. connectio1'i,'30, leading from of the pipes. 1;) and "0respectively. Salt is drawn trom the evaporator, (i, by closing thvvalve. Il. and opening the cover, 7T, on the chamber. T2. ,it TS, Fig.3, 1s ntdl Iated a spray of water dropping from a pertoration. l). inthv pipe, lll. to the pan, S. The

sprays trom all the pertorations drop to the pans in the mannerindicated by this spray. TS.

ln the operation ot' the 4apparatus the pipes 1l are iillvd with waterandpumps 23 started to force the water intoA pipes 10. Steam pressure inthe boiler Il, is maintained preterably at about 200 lbs. The engine 2,receives the live steam at this pressure and exhausts at about (3() lbs.pressure through the valve. t4() into the steam pi ies, ofv the grainvr.Il. The brine supplie to the g is maintained constantly at the levelindicated by the line. o5, thv ,sub1nerged steam pipes heat this brineto about 270 degrees.

Tl and T5. correspond to thoseainvr through any suitable connection As'270 degrees is considerably lower than boiling point ol brine at thelpressure of about 5t) lbs. (which is the pressure ot' the au'compressed inv thv upper partof the grainvr. il) there will beno'ebullition but' evaporation takes place at the surface where thebrine is in contact with the air. The t'ans itl. circulate theconned'air'causing thv air which is now laden with aqueous vapor to flowthrougl-i the spray falling from the perforated pipes, 10, 1t), into thetroughs, tl. b'.

with the air and becomes heated to a temperature approaching thatot' thevapor. The

spray is collected in the troughsand flows to the header l1', then tothe pipe, lf2, to

Obviously this spray of water condenses some ol the apor which 1scombined gli the pipes. T, ot' the grainer, l. The heat absorbed at thespray is here transmitted to' the brine surrounding thesel pipes, 7,(otl the courses through these pipes, instead ot' the pipes being heatedby steam as in the grainer 3, aside. 'from this feature and the factthat the internal pressure in thc grainer is about at atmospheric whilethe temperature is about 190i degrees the operating conditions areidentically the same as are those in the grainer, 3. The same operatingconditions 'prevall in 'the gralner, 5, as 1n the grainer except'thatthe temperature of the I brine is 160 degrees. 1 The hot circulatingwater-issuing from the grainer, 5, flows mitted to" the boiling brine inthe vacuum space of this evaporator. The lcirculating water after giving'up some of its containedl b heatreturns by the'pipe, to the centrifugalPump, 23, of the grainer, 5. The vapor. from the boiling brine ascendsto the condenser,A

5l, and is condensed, the entrained air is taken out by the yacuumpump.`

I' do not confine the process tov operate only-at the pressuresandtemperatures above given. "There are times that a somewhat smaller grainsalt is desired and again a Very large grain is necessary to supply therequirements of the market. Rapid evaporation due to workingv withhigher temperatures will tendvto make the smaller grain and a lowpressure and temperatures will make the larger. grain. For instance,steam could be lfed direct from the boiler through the valve, 59, intothe pipes, 7. A higher temperature would be given to the brine, in thegrainer, 3, (a higher air pressure could be carried in the grainers, 3,and 4, also) and a more rapid evaporationvresult. The grainers, 4 and 5would also receive hotter circulating Water with an effect of anincreased rate of evaporation. The evaporator 'would also receive hottercirculating water from the grainer, 5. On the other hand when very largegrain salt is. desired the pressure and temperatures along the Wholeline can be lowered in proportion so that a much slowerevaporation wouldbe carried on and the production would be a much i' larger grain salt.

Itis not necessary to use the exhaust of the engine for heating unlessso desired. The boiler pressure can be carried much lower' than the 200lbs. I prefer and the exhaust of the engine discharge to atmospherethrough the valve, A61. The valve, 60, is closed and live steam is fedinto the pipes 7, through the valve, 59, directly from the boiler 1.

What claim as my invention isi. The process of effecting a series ofsurface evaporations of brine at temperatures below the boiling pointsconsisting of heating the first body of brine, evaporating in contactwith air, absorbing heat from the fcombined air and vapor in water andutiliz- `ing the heated water to effect a second surface evaporation.

2. The process of evaporating. brine consisting of effecting a surfaceevaporation at apressure above atmospheric by confining lair underpressure above .and in contact with the surfaoepf the body of heatedbrine, circulating the air andy combining vapor with saidair'andseparating the vapor from the combination by condensing.

3. The process of e`ecting a series of evaporations without agitationconsisting of maintaining heated bodies of brine in surface contact withconfined bodies of air, and absorbing heat from the first of the seriesto effect an evaporation in the second.

4t. In the process of recovering salt from brine the effecting of aseries of surface evaporations by successivelv heating bodies of brinewhich are in surface contact with air by absorbing the heat contained inthe vapor rising into the air from the first bodv in sprays of water andthen utilizing said 'heat by collecting said sprays into a single columnof flowing water and causing same to heat a second body.

5. In the process of recovering salt from brine the effecting of aseries of surface evaporations by -successively heating two bodies ofbrine which are in surface contact W1th air, the ai-r pressure in thefirst being higher than that in that ofthe second, by absorbing the heatcontained in the vapor rising into the air from the first body in spraysof Water and then utilizing said heat by collecting said sprays into asingle column .of flowing water and causing same to heat a second body.

6. In the process of recovering salt from brine the effecting of a.series of surface evaporations by successivelv heating three bodies ofbrine which are in surface contact with air, the air pressure in thefirst being higher than that of the second and the air pressure of thesecond and third being the same, by absorbing the heat contained in thevapor rising into the air from the first body 105 in .sprays of waterand then utilizing said heat by-collecting said sprays into a single icolumn of flowing water and causing sameg to heat a second body, thenabsorbing the heat contained in the vapor rising into the air from thesecond body in sprays of vv iter and then utilizing said heat by collec.'ng said sprays into a single column of flowing water and causing sameto heat a third body.

7. The process of recovering salt from brine consisting of effecting aseries of bevapor arising ,therefrom and absorbing the 13G heatcontained therein by sprays of water, collecting' said sprays of waterand causing .same to etl'ect a second lower than boiling, point surfaceeranoration from a second body oi' brine in surface contact with air atatmospheric pressure, condensing the vapor arisinigr therefrom andabsorbing the heat thereof by sprays of water, collecting saidcollecting said sprays of Water and causing same to effecta second lowerthan boiling point surface evaporation from a second body of brine insurface Contact, with air at atmospheric pressure, condensing the vaporarising therefrom and absorbing the heat;

thereof by sprays of water, Collecting said sprays ot' water and causingsame to eiect a third lower than boiling point surface e Vapor-ationfrom a third body of brine in surface contact with air at atmosphericpressure condensing the vapor arising therefrom and absorbing the heatcontained therein by sprays of water and causing same to effect a fourthevaporation at the boiling point due to a vacuum.

FRANK J. WOOD: \Vitnesses MICHAEL VALSIL- CHARLES RAGGE.

